David Epstein’s day-by-day forecast for the coming thaw and rain

The combination of rain and melting snow means the possibility of more flooding, just on the heels of last week’s inundation of ocean water during the storm. –Dina Rudick/Globe Staff

Temperatures on Wednesday morning were quite chilly across the region, but certainly not the arctic cold of last week. And that thaw you’ve been hearing about is coming: Thursday will get into the upper 40s to perhaps the lower 50s. This will be followed by a rainstorm Friday into early Saturday.

The combination of rain and melting snow means the possibility of more flooding, on the heels of last week’s inundation of ocean water during the storm.

This map shows how much water is locked up in the snow across the Northeast as of early Wednesday morning.
Heavy downpours are likely as 1 to 3 inches of rain falls from early Friday to early Saturday in New England.

It doesn’t take much rain in the winter to create street and basement flooding. The ground is frozen and can’t absorb much water. While the snowpack will soak up some of the rain, much of it will run into the streets and perhaps into some of our homes.

Double shot of rain

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It’s a complicated forecast this weekend because there’s not just one area of rain on the way, but two. The first round is the heavy rain early Friday. We may eek out the morning commute without much rain, but it should be pretty wet for the rest of the day.

There’s going to be a break in the heavy rainfall for a few hours Friday evening. I’m not sure whether the rain will stop or just lessen a bit, but it won’t be as heavy. If you watch the animation below, you can see a brief gap in the rain as it moves through Friday and Saturday.

A second round of rain associated with a low-pressure area will then move in for late Friday night and early Saturday. The track of this low-pressure area will determine not only how much rain we get but whether we see a bit of frozen precipitation as the storm ends.

Each of those little L’s represent a possible track of low pressure. The closer together they are, the better the agreement of the models. —WeatherBell

Cold follows the rain

We’re going to have to watch if the cold air rushes in early enough to bring some freezing rain or sleet at the end of the storm. The most likely places for this would be far Northern Massachusetts and into northern New England. However, if the storm track changes and moves south, even the northern and western suburbs of Boston could see some freezing rain at the end of this storm.

If you’re traveling this weekend, especially Saturday, know that conditions could become quite hazardous the further north you go, especially in ski country. . This could turn into a dangerous ice storm for parts of Vermont, New Hampshire, and Maine.

Freezing rain and sleet will be an issue Saturday over northern New England.
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As the system moves out of the area, the precipitation will end and it will turn quickly colder. A freeze will return, and any slush or standing water will turn to ice pretty quickly.

Dry and cold playoff games

All of this should be over well before the Patriots kickoff. If you are headed to the game you’ll definitely want to bundle up, as temperatures will be below freezing, though not as cold as recent games.

Sunday and Monday look dry and chilly, and cold weather should continue much of next week with some chances of snow, but I don’t have anything definitive enough to put into the forecast just yet.

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March 31, 2018 | 8:47 PM